Merge branch 'ExprEval' into 'master'

Added ExprEval application.

Hi, here is the metadata file for my simple math application.

Upstream:  https://github.com/gianluca-nitti/android-expr-eval

All code is MIT-licensed.

See merge request !1895

metadata/com.github.gianlucanitti.expreval.txt

@@ -0,0 +1,33 @@
+Categories:Science & Education
+License:MIT
+Web Site:
+Source Code:https://github.com/gianluca-nitti/android-expr-eval
+Issue Tracker:https://github.com/gianluca-nitti/android-expr-eval/issues
+
+Auto Name:ExprEval
+Summary:Math expression calculator with variables and functions support
+Description:
+Application that solves math expressions. Main features:
+
+* Supports variables (e.g. you can do "a=5", then "a+1" and you get 6)
+* Built-in basic function (like logarithms and trigonometry)
+* Custom functions can be defined (e.g. "log(x,b)=log(x)/log(b)", then log(32,2) will print 5)
+* Variables and unctions can be edited both from the prompt and dialogs
+* Can print parsing and evaluation steps.
+
+This application is based on [https://github.com/gianluca-nitti/java-expr-eval
+this] open source (MIT licensed) library.
+.
+
+Repo Type:git
+Repo:https://github.com/gianluca-nitti/android-expr-eval.git
+
+Build:1.0,1
+    commit=v1.0
+    subdir=app
+    gradle=yes
+
+Auto Update Mode:None
+Update Check Mode:Tags
+Current Version:1.0
+Current Version Code:1