Integrate PDGs created by Flowistry (#119)

## What Changed?

- Data and control flow graph construction moves into the Flowistry
crate.
- Removes `df`, inlining logic and the algebra.
- Entails an update of the rustc toolchain (to achieve parity with
flowistry).
- Graph contains all program locations, not just function calls.
- Control flow is non-transitive
- The PDG now tracks individual places instead of abstract function
arguments. This improves field sensitivity across function calls.
- Forge output is gone

## Why Does It Need To?

Field sensitivity is now handled as the initial analysis constructs the
PDG and in fewer lines of code.

## Caveats

At the time of this merge, the following regressions in the PDG have not
been fixed yet

- willcrichton/flowistry#95
- willcrichton/flowistry#94
- willcrichton/flowistry#93
- And while Will fixed the strong updates
willcrichton/flowistry#90 the second issue
mentioned there is still present.

## Checklist

- [x] Above description has been filled out so that upon quash merge we
have a
  good record of what changed.
- [x] New functions, methods, types are documented. Old documentation is
updated
  if necessary
- [ ] Documentation in Notion has been updated
- [ ] Tests for new behaviors are provided
  - [ ] New test suites (if any) ave been added to the CI tests (in
`.github/workflows/rust.yml`) either as compiler test or integration
test.
*Or* justification for their omission from CI has been provided in this
PR
    description.

.github/workflows/rust.yml

@@ -41,38 +41,6 @@ jobs:
     - name: Run tests
       run: scripts/compiler-tests.sh
 
-  intergration-tests:
-    name: Integration Tests
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v3
-    - name: Build Compiler
-      run: cargo build --verbose
-    - name: Cache Racket dependencies
-      uses: actions/cache@v3
-      with:
-        path: |
-          ~/.cache/racket
-          ~/.local/share/racket
-        key: ${{ runner.os }}-integration-tests-${{ env.racket_version }}-${{ env.FORGE_REVISION }}
-    - name: Install Racket
-      uses: Bogdanp/[email protected]
-      with:
-        architecture: 'x64'
-        distribution: 'full'
-        variant: 'CS'
-        version: ${{ env.racket_version }}
-    - name: Install Forge
-      run: |
-        cd ..
-        git clone https://github.com/tnelson/Forge
-        cd Forge
-        git checkout ${FORGE_REVISION}
-        cd forge
-        raco pkg install --auto || raco setup forge
-    - name: Run Tests
-      run: scripts/integration-tests.sh
-
   format-check:
     name: Format Control
     runs-on: ubuntu-latest
@@ -132,4 +100,10 @@ jobs:
           target/
         key: ${{ runner.os }}-rust-deps-${{ hashFiles('Cargo.lock', 'rust-toolchain.toml') }}
     - name: Here come the complaints
-      run: scripts/doc-check.sh
+      run: scripts/doc-check.sh
+
+  integration-tests:
+    name: Integration Tests
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3

.gitignore

@@ -10,4 +10,9 @@ flow-graph.json
 *.info.json
 
 # Delete this if we want to include a rustfmt configuration
-.rustfmt.toml
+.rustfmt.toml
+
+/.idea/
+
+.DS_Store
+*.flowistry-pdg.pdf