DOC: Added instructions for Azure Linux (#567)

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### Summary   
Added Azure Linux instructions to the README.md

Author: jonmclean

README.md

@@ -38,6 +38,9 @@ zypper install -y libltdl7 libkrb5-3 libgssapi-krb5-2
 # For SUSE/openSUSE
 zypper install -y libltdl7
 
+# For Azure Linux
+tdnf distro-sync && tdnf install -y libtool-ltdl krb5-libs glibc-iconv
+
 pip install mssql-python
 ```