Update dependencies, min Rust version to 1.29.2

.appveyor.yml

@@ -7,7 +7,7 @@ environment:
   - TARGET: x86_64-pc-windows-msvc
     CHANNEL: stable
   - TARGET: x86_64-pc-windows-msvc
-    CHANNEL: 1.26.2
+    CHANNEL: 1.29.2
   - TARGET: x86_64-pc-windows-gnu
     CHANNEL: stable
   - TARGET: x86_64-pc-windows-gnu

.travis.yml

@@ -3,7 +3,7 @@ rust:
   - stable
   - beta
   - nightly
-  - 1.26.2
+  - 1.29.2
 cache: cargo
 dist: trusty
 sudo: false

README.md

@@ -6,7 +6,7 @@ Building
 --------
 DeltaMap is written in Rust, so you will need to [install
 Rust](https://www.rust-lang.org/install.html) to compile the program. The
-minimum supported version of Rust for DeltaMap is **1.26.2**.
+minimum supported version of Rust for DeltaMap is **1.29.2**.
 
 On Linux you will also need OpenSSL with headers.
 (see <https://docs.rs/crate/openssl/0.10.12> for details)