Incorrect syntax highlight with string interpolation

[JefStat]

Environment data

dotnet --info output:

.NET Command Line Tools (1.0.0-preview1-002702)

Product Information:
Version: 1.0.0-preview1-002702
Commit Sha: 6cde21225e

Runtime Environment:
OS Name: Mac OS X
OS Version: 10.11
OS Platform: Darwin
RID: osx.10.11-x64

VS Code version: Version 1.2.0 (1.2.0)
C# Extension version: 1.1.4

Steps to reproduce

Use string interpolation with escaped double quotes

Expected behavior

Correct syntax highlighting.

Actual behavior

[abdullah2993]

+1 for this one for

Environment data

dotnet --info output:

.NET Command Line Tools (1.0.0-preview1-002702)

Product Information:
 Version:     1.0.0-preview1-002702
 Commit Sha:  6cde21225e

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.10586
 OS Platform: Windows
 RID:         win10-x64

VS Code version: 1.2.1
C# Extension version: 1.1.6

[lennylxx]

+1 for this #450.

[DustinCampbell]

This is a duplicate of #249. We'll use that issue to track this bug.